Composition of matter for photographic processes



Fatented Fehi 5, lQZd.

' STATES QDFFHQEO RQBERTJUHN, GE NEW YORK, N. Y., ASSIGNOR T0 DAYLIGHTFILM CtlRPQELATIQH, A CORPOBATION OF NEW YORK.

CGMPOSITION 0F MATTER FOR PHOTUGRATPHIC IPBDCESfiEQ.

Ho Drawing. Original application filed may a, 1916, Serial Ito. 95,535?Divided and this application filed July 2Y5, 1919.

To all whom it may concern:

Be it known that l, Bonner JOHN, a citizen of the United States,residing at New York, in the county of New York and State of New York,have invented a certain new and useful Composition of Matter forPhotographic Processes, of which the following is a specification.

My invention relates to a composition of matter for photogra hicprocesses and has for its object to pro uce a printing surfacecontaining a photographic record of lights and shades from W ich copiescan be made by a dye or ink contact transfer process.

An illustrative dye contact transfer process is disclosed in patent toShepherd and Bartlett No. 728,310, granted May 19, 1903, forphotographic printing, and an illustrative ink contact transfer processis disclosed in Cassells Cyclopaedia of Photography, Cassell & 00., NewYork, 1912, at page 1% under the title Collotype, it being understood,however, that the processes thus illustrated do not disclose a printingplate having the novel and beneficial characteristics of the printingplate obtained by the-use of the composition of matter disclosed andclaimed herein. Although the preferred method is to obtainthe'photographic record for the printing surface from a completednegative, it 1 may be obtained by direct exposure, as, for-example, in acamera, the details of which method are disclosed in a copendingapplication for Letters Patent Serial No. 327,890, filed October 2,1919, for process of photographic reproduction directly from a negative.The printing surface when treated with dye or ink also may be used inthe same manner as a positive,

either for direct view, or with reflected light, or with transmittedlight as in a projecting machine. I

This application is a division of my copending application for LettersPatent Serial No. 95,957, filed May 6, 1916, for

photography.

The invention is applicable to monochromatic, polychromatic, or naturalcolor photography both in still photogra by and in motion picturephotography. 1e term color is intended to include black, which"sometimes technically is designated as an absence of color.

Serial lilo. 813,238.

lln the embodiment of my invention chosen for purposes of'illustration,a sensitized emulsion such as a silver salt emulsion is exposed to theaction of light modified by the lights and shades of the completednegative which it is desired to reproduce. The silver salt emulsion maybe carried or mounted on any desired support, either opaque,translucent, or transparent, but preferably is mounted on a transparentcarrier such, for example, as glass or a cellulose base, in order thatthe the silver salt emulsion may be exposed to the moditied lightthrough its transparent carrier.

The emulsion then is treated by a developing solution containing ahardening or tanning agent which hardens or renders insoluble orunremovable the emulsion adjacent its light adected, light sensitivecontent, the effect of which agent is controlled or limited selectivelgby the presence oi varying quantities o a neutralizin agent, after whichthe unhardened or soluble or removable portions of emulsion are removedin any des1red manner, as, for example, by melting with warm water.

The result of the above treatment is production or what may he termed aprinting surface having novel characteristics and beneficial propertiesnever before attained. I

The most important of the novel characteristics is a printing orreproducing surface comprisinggranules or great numhers of photoraphically formed, cntremelyminute, in ividual protuherances which aredistributed and grouped irregularly so as to represent photographiclights and shades.

The most important. of the beneficial properties is that such a printingsurface when treated with a dye, inlr, or other coloring matter, willabsorb or take up or carry the coloringmatter within a few seconds, andwhen thus treated and placed in contact with a substance which is tocarry the final reproduction, such for example as a gelatin, will giveup its coloring matter practically instantaneously and produce on saidgelatin an exact and perfect reproduction. This speedy result, which isnovel and was impossible of attainment before the present invention, isof prime importance in the production of motion picture posiilll Watera; 8.5 ozs. P rogallic acid l1 grs.

etol 9 grs. Potassium bromide -s 4 grs. Sodium carbonate 200 grs.

Sodium sulphite "40 to 60 grs.

In the above sample formula the hardening ortanning agent is pyrogallicacid, and the controlling and limiting agent is sodium sulphite whichmay be: varied in amount selectivelywithin limits to obtain the desiredresult. It is well known: that pyrogallic acid also is a developingagent and that sodium sulphite is a preservative adaptedtoprevent'oxidation of the pyrogallic acid in solution.: Other hardeningand tanning agents and other neutralizing agents may be used, the aboveformula representing one developing solution by which the process may becarried out; Potassium bromide, for example, also has a certaincontrolling and limiting effect. The main difference betweenthe abovesample formula and standard developing formulas is in'the amount ofsodium Csulphite used. ln

standard formulas the amount of sodium sulphite used is so greatly inexcess of the amount used in the above sample formula that. the tanningor hardening effect of the pyrogallic acid is'entirelv neutralized orovercome. In the sample formula, the sodium sulphite merely controls andlimits the hardening effect of the pyrogallol. It *is of courseunderstoodyby those skilled in the art that when a thick layer ofemulsion is treated, or when the exposure is through the transparentcarrier, it is advisable, in order to accelerate the action of thepyrogallic acid, to use larger quantities of an accelerator such, forexample, as sodium carbonate or its equivalents than when the emulsionlayer is thin or exposed on its face. When larger quantities of sodiumcarbonate thus are used, it is necessary to increase the amount ofsodium sulphite. The above sample formula is for treatment of anemulsion exposed through its transparent carrier and therefore containsa comparatively large amount of sodium carbonate with an increasedamount of sodium sulphite. In order to obtain the dethe selectlvehardening desired.

It is believed that the hardening or tanning effect of the pyrogallicacid exerts its action first adjacent the so-called latent ima e, or inother words, on the portions of emu sion adjacent the particles ofsilver salts affected by the exposure light and converted by thedeveloper into metallic silver. Thus in a silver bromide film, thethrowing off of the bromide from a light affected silver bromideparticle in the developing process, probably reacts with the pyrog icacid to harden ortan or render insoluble or unremovable the adjacentemulsion. Thus in the embodiment chosen for purposes ofillustration,'the reaction roducts from the chemical effects of theeveloper solution, are believed to react with the selectively controlledhardening agent. However this may be, it is necessary for purposes of myinvention only either to harden particles of emulsion adjacent lightaffected particles of the light sensitive content in any desired manner,

or in reverse manner to leave unhardened the particles of emulsionadjacent light afiected particles of the light sensitive content andharden the remaining emulsion, the essential result being a hardenedemulsion surface corresponding to the lights and shades to be reproducedwhich will acquire and give up any desired color in a com arativelyshort time. By controlling the liardening or tanning effect of thepyrogallic acid as above set forth, only the particles of emulsionadjacent the said light affected particles of silver salts are hardened,the relative proportions of the hardening'agent (whether or notaccelerated by an accelerating agent) and of the neutralizing agentbeing such as to control selectively the effective area of influence ofthe'hardening agent. The unhardened portions, as 'stated above, then maybe removed in any desired manner as by placing the emulsion in warmwater which causes the unhardened or soluble portions to soften and meltaway from the hardened or insoluble portions so that the hardenedemulsion alone will remain in the form of extremely minute, individualprotuberances which are distributed and grouped irregularly so as torepresent the photographic lights and shades which it is desired toreproduce. It is preferable that measleonly those portions of emulsionbe hardened which are adjacent the carrier for the emulsion, which maybe accomplished in various ways, some of which are disclosed in mycoending applications for Letters Patent erial No. 313,239, filed July25, 1919, for a thin mounted sensitized emulsion; Serial No. 313,240,filed July 25, 1919, for proeess of making a contact transfer printingsurface by complementary light; Serial No. 327,891, filed-October 2-,1919, for potassium iodide formula for photographic processes, processof using same, and article obtained thereby; Serial -No. 332,806, filedOctober 23, 1919, for process of making a contact transfer printingsurface with a colored emulsion, and among which ma be mentioned theexposure of'the sensitized emulsion through its transparent carrier andthe limitation of the depth to which the rays of exposure lightpenetrate by having the actinic emulsion complementary in color.

If desired the hardened emulsion may be fixed to remove the silver saltsunadected by light, and bleached to remove the black metallic silver.This may be done in well known manner, and While not necessary, is ofadvantage as it enables the operator to watch the sheet of the coloringmatter on the printing surface to which it is applied for carrying outthe printing process.

The order of melting, bleaching, and fixing is not important and ma becarried out in any order desired, althoug it enerally is more convenientto fix, melt, an bleach, in the order named.

, The printing of positives from the printing surface may be done bydirect contact. The printing surface is exposed to the action of thedesired coloring matter as by placing it in or carrying it through aliquid color bath. The colored surface then is placed in contact,preferably under some pressure, with the substance on which the positiveis to be made, asby a roller by a squeegee action. As stated above, theprinting surface prepared by my process receives and gives up thecoloring matter almost instantl as distinguished from other processeswhich take an appreciable length of time.

Natural color effects may be produced in well known manner, such forexample as by exposure through color screens with subsequent treatmentand manipulation to obtain the desired results.

Many modifications of m invention will be apparent to those ski led inthe art without departing therefrom or from the scope of the claims, myinvention not being limited to the embodiments thereof chosen i'orpurposes of illustration but consisting of a composition of matter forforming a printing surface capable of acquiring and giving up a desiredcolor with great rapidity.

rays of the exposure light and the By the term metol in this case ismeant monomethylparamidophenol sulphate or its equivalents. I

Having described one, embodiment of my invention, what I claim is:

1. A developing and hardenin composition of matter containing an emusion hardening andsilver salt developing substance and a substancepartially but not entirely neutralizing the emulsion hardening effect ofsaid developing and hardening substance in such amount as to ,permitonly a selective areaof hardening.

2. A developing and hardening composition of matter containingpyrogallic acid and a substance partially but not entirely neutralizingthe-emulsion hardening effect of said pyrogallic acid in such amount asto permit only a selective area of hardening.

3. A developing and hardening composition of matter containing pyroallic acid and sodium sulphite in which t e amount of sodium sulphite issuflicient only to control but not eliminate the hardening efiect or thepyrogallic acid.

4. A gelatin hardening composition of matter containing an emulsionhardening substance and a substance partially but notentirelyneutralizing the emulsion hardening etl'ect of said hardening substancein such amount as to permit only a selective area of hardening.

5. An emulsion hardening composition of matter containing pyrogallicacid and a substance partially but not entirel neutralizing the emulsionhardening eilect of said pyrogallic acid in such amount as to permitonly a selective area of hardening.

6. A developing and hardening composition of matter containing water,pyrogallic acid, metol, otassium bromide, sodium carbonate, and sodiumsulphite in which the amount of sodium sulphite is sufiicient only tocontrol but not eliminate the hardening effect of the pyrogallic acid.

A developing and hardening composition of matter containing grs. Sodiumsulphite 40 to grs.

8. A developing and hardening composition containing pyro allic acid,sodium sulfite and sodium car onate, in which the sulfite is present onlin suilicient quantity to control but not e iminate the hardening effectof the pyrogallic acid.

9. A developing and hardenin composition containing pyro llic aci sodiumsulfite and sodium car onate, in which the ratio by weight on the drybasis, or carbonate to sulfite is greater than 3:1 and in which thesulphite is present only in sufiicient quantity to control but noteliminate the hardenin efiect of the pyrogallic acid.

10. A deve oping and hardenin com osition containing pyrogallic aci soium sulfite and sodium carbonate, in which the ratio by weight, on thedry basis, of carbonate to pyrogallic acid is about 10:1

and in which the sulphite is present only in in sufficient quantity tocontrol but not eliminate the hardening effect of the pyrogallic acid.

In testimony that-I claim the foregoing,

I have hereunto set my hand this 23rd day 15 of July, 1919.

ROBERT JOHN.

